[llvm] [llvm] Add KnownBits implementations for avgFloor and avgCeil (PR #86445)

[Simon Pilgrim via llvm-commits]

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@@ -826,7 +826,7 @@ TEST_F(AArch64SelectionDAGTest,
   EXPECT_EQ(KnownAVGFLOORU.One, Ones);
 
   SDValue AVGFLOORS =
-      DAG->getNode(ISD::AVGFLOORU, Loc, Int16Vec8VT, ZextOp0, ZextOp1);
+      DAG->getNode(ISD::AVGFLOORS, Loc, Int16Vec8VT, ZextOp0, ZextOp1);
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RKSimon wrote:

I thought I'd fixed this diff in 6acc50ae5b5971af563a0f40b5f0279870171541 ? Please can you rebase

https://github.com/llvm/llvm-project/pull/86445